Hello,
Molina already mentioned the rules thing, so I will skip that
1) There is no real downside, except for the price. If you already want to get a Recharge Port, I'd always go for the port plus the 1.2A charger then.
2) Yes, the port is the same for the 0.2A and 1.2A chargers.
3) I never tried that so far, so I can't tell you. But hteoretically it should be possible.
4) Always 2 there are...not more, not less...a master and an apprentice - oops, sorry for that
But it's correct, you need exactly 2 of them.
(Btw: You don't happen to be from Germany? Your name sounds like that...)